Emperor Xuanzong of Tang

Emperor Xuanzong of Tang (8 September 685-3 May 762) was Emperor of Tang China from September 713 to 12 August 756, succeeding Emperor Ruizong and preceding Emperor Suzong. He was the last Tang emperor to preside over the dynasty's golden age, which was ended by the An Lushan Rebellion of 755, caused partly by Xuanzong's reliance on the dictatorial chancellor Li Linfu and the drunkard cousin of his concubine Yang Guozhong to run the state as he focused on religion and romance. He was deposed by his own son in 756 and died six years later.

Biography
Li Longji was born in 685 AD, the son of Emperor Ruizong of Tang and Wu Zetian, and his mother ruled over the country from 690 to 705 after ousting her husband from power. In 705, Wu Zetian was ousted in a military coup and succeeded by Li Longji's uncle Li Xian, who became known as Emperor Zhongzong of Tang, and he died in 710 AD, upon which Ruizong was restored to power. In 713, Ruizong died and his son Li Longji became "Emperor Xuanzong".

Reign
Xuanzong's age saw the apex of the Tang Golden Age, during which poetry and artwork flourished, an export industry developed, and Indians, Persians, Arabs, Koreans, Syrians, Sogdians, and others became merchants in the capital and worshipped in their own manner. Early in Xuanzong's reign, many of the greatest works of the period were created. In 736, Li Linfu was appointed Chief Minister, and Xuanzong let Li Linfu take over administration as he focused more on religion and his favorite courtesan. During the 740s, Li Linfu purged political rivals and became a dictator by 747 AD. However, he gave command of China's armies to Turkic generals in an attempt to prevent political rivals from holding military leadership positions, leading to the military being disloyal to the government. Xuanzong was influenced by his courtesan to appoint several of her relatives to leadership positions at court, and her cousin Yang Guozhong affiliated himself with Li Linfu's rivals and plotted to remove Li Linfu's ally An Lushan from his command over 164,000 troops at Fanyang (present-day Beijing). When Li Linfu died in 753, An Lushan grew concerned that he would lose his command and favor at the court. In 755, An Lushan rose in rebellion against the Tang, capturing Luoyang in 756. Xuanzong made the mistake of having his able generals Feng Changqing and Gao Xianzhi executed for failing to hold the city, and he then sent the army to attack Luoyang at Yang Guozhong's advice. The army was destroyed, and, with Tong Pass open and Chang'an vulnerable, Xuanzong and the court were forced to flee towards Chengdu. Along the way, soldiers returning from the defeat massacred Yang Guozhong, Consort Yang, and their family, blaming them for their loss. After Xuanzong arrived in Chengdu, his son and heir Suzong, who marched north to Lingzhou, usurped the throne from his father, ending the Tang's longest reign. He died in 762 at the age of 76.